Naidelys Montoya didn't wait for her son's baby teeth to fall out. She took the boy to an oral surgeon to have two of the loose ones extracted.

"He was a bit scared," said Montoya, of Hialeah, Fla. "He's not that brave."

The dentist shipped the teeth in a temperature-controlled steel container to a lab in Massachusetts, where their stem cells will be spun out, frozen to more than 100 degrees below zero and stored -- in case her son, Raul Estrada, 6, might need them for a future illness.

"I believe in this," his mom said. "I did it as a precaution against things that could happen."

Montoya and her son have joined a new medical movement. Some dentists are extracting baby teeth, wisdom teeth and even healthy adult teeth, and researchers are spinning out stem cells that they believe can be used to regrow lost teeth, someday even to repair damaged bones, hearts, pancreases, muscles and brains.

It could put the Tooth Fairy out of business.

"These are teeth we've been discarding as dental waste," said Dr. Jeffrey Blum, the Miami Beach oral surgeon who pulled Raul's teeth. "We might as well get some use out of them."

"I can't help but feel excitement for their potential use in regenerating different tissues in the human body," said Dr. Jeremy Mao, director of the Regenerative Medicine Laboratory at Columbia University. Mao also is chief science adviser to StemSave, a New York City company that freezes the stem cells and stores them for later use.

In Minnesota, the idea is still in the research phase. The Stem Cell Institute at the University of Minnesota is experimenting with cells extracted from teeth but doesn't anticipate being able to grow new teeth -- or anything else -- from them anytime soon, said Dr. Dan Kaufman, the institute's associate director.

"It's an active area of research in which we're collaborating with the [university's] Dental School," he said. "As a future form of therapy, perhaps. But not now."

There are concerns about the practice. It's expensive, costing $590 upfront plus $100 a year to store the stem cells from up to four teeth for up to 20 years. It's speculative, with the first FDA-approved practical use of such stem cells years away.

"Every treatment using dental stem cells is still in the clinical testing phase, and won't be ready for general use for at least five years," said Art Greco, StemSave's CEO.

The National Institutes of Health concluded in 2003 that teeth are a rich source of stem cells. Every child has about 20 baby teeth that fall out between ages 6 and 12. Adolescents have wisdom teeth that often are removed between ages 14 and 25 because they crowd the jaw or grow in crookedly.

Blum and other oral surgeons must extract baby teeth before they fall out naturally, so they still have a blood supply to keep them healthy. He puts them in a temperature-controlled steel container and overnights them to the StemSave facility.

"Perhaps it does make sense to save" dental stem cells, said Dr. Joshua Hare, director of the Interdisciplinary Stem Cell Institute at the University of Miami Medical School, who is not involved with dental stem cells. "Within human adults and children there are lots of reservoirs of stem cells. We get them from bone marrow; others use umbilical cord blood. It seems teeth are also a good source."

Stem cells are the body's repair system, Hare said. Stem cells beneath the skin are constantly spinning off new skin cells to replace skin that is sloughed off or damaged in daily life. The same is true for hearts, livers, pancreases -- except that as the body weakens from age, injury or disease, those stem cells lose the ability to keep up and need help. Today, stem cells from bone marrow, blood and now perhaps teeth can be reprogrammed to help those ailing organs.

Also, by using these stem cells, researchers avoid involving human embryonic stem cells, which are controversial because their creation involves destroying human embryos.

The American Dental Association, while cautiously optimistic about the potential of dental stem cells, urges parents considering banking their children's dental stem cells to consider both the cost and the rarity of use before joining private donation programs.

"That's the question people have to ask themselves," Blum said. "Am I saving this for no reason? Is it worth what I'm paying? Essentially, it's an insurance policy."

Sure, holiday baking traditions are great. But isn't it time to try a new sweet treat this year? The Holiday Cookie Finder has every winning recipe from our annual baking contest from the past 14 years.

It's tempting to drop everything and roam Minnesota to catch all the crimsons and golds at this time of year. But who has time for that? We've found your leaf-peeping match. Just follow our flow chart.